Here are minutes of our meeting on Thursday -- please just reply with (or let me know) any corrections -- thanks!:
Attendees: Yorke Brown (Dartmouth), Arnold Gaertner (NRC), Cordell Grant and Houman Hakima (UTIAS-SFL).
Yorke and his students Cynthia and Maggie are preparing for the initial flights this year, with a tethered balloon drop test done jointly with the Greencube group to be done later this week (weather permitting) and the goal for our first free flight this year being the second full week in May. The flux from the diffused light source is currently being re-measured in the Wilder lab next door to Yorke's to get a new O(5%) uncertainty measurement on that. I'll be out in Hanover May 6 - 18 and will help with flights during that time etc.
Here at UVic, Karun, students Nic Loewen and Marlene Machemy, and I did a 10 km Mt. Tolmie to Observatory Hill test this past Monday evening of the 532 nm laser and 144 MHz radio possible backup communication systems. The 144 MHz radio test (photos at http://projectaltair.org/HyperNews/get/AUX/2015/03/02/21.27-45306-144MHzBoards1.jpg and http://projectaltair.org/HyperNews/get/AUX/2015/03/02/21.27-63467-144MHzBoards2.jpg) was successful, in that Mt. Tolmie could receive data from the Observatory Hill location, but transmission in the other direction was not received -- probably due to my inability at Mt. Tolmie to hold the antenna stretched out vertically and type at the same time. We should perhaps repeat with better antennas (or perhaps with the same antenna we use for the MURS locator, if that can be dual-used). Our optical test had low signal/noise, due to difficultly at the Observatory Hill end in affixing the photodiode onto the eyepiece of a spotting scope, and also due to some noisy AC power. We'll try again once those issues are fixed later this week. We have also started to make an electronic-actuated helium bleed valve to used with our latex weather balloons -- an idea borrowed from this site: http://www.benoxley.com/b/altitude_controller_report.pdf. Such a valve requires significant aperture to vent a decent volume of helium within a few seconds, but of course must be lightweight, very low power, and low DC voltage -- thus we are using this 1.5" Valterra gate valve: http://www.grainger.com/product/VALTERRA-Gate-Valve-4HGE8 and making a little actuator for it with the same motor and photogates Yorke uses for the cutdown: http://altair1.dartmouth.edu/docs/specsheets/Motor-159418.pdf and http://altair1.dartmouth.edu/docs/specsheets/OPB960-990.pdf . Mark Lenckowski has now designed this for us, per these photos: http://projectaltair.org/HyperNews/get/AUX/2015/04/26/21.12-70310-balloonvalve1.jpg , http://projectaltair.org/HyperNews/get/AUX/2015/04/26/21.12-97879-balloonvalve2.jpg , http://projectaltair.org/HyperNews/get/AUX/2015/04/26/21.12-18702-balloonvalve3.jpg , and we'll make it when I get out to Hanover in a couple weeks.
Houman has now completed the design of the mounting of the LED additional sources, and their little power supply board, to the integrating sphere, and has also essentially completed writing up the work up in his master's thesis. He is waiting for Cordell's approval of his latest drawings, and then will send it around and post more info and pictures of it, and will ask us any additional questions if any come up.
The JHU group attempted to join the telecon, but a few minutes after we ended the brief meeting, so we'll look forward to a report from them next time (May 7). Their aircraft and light source are working well in laboratory tests, they'll soon be doing some further test flights below the 400 ft altitude limit, and they'll send a video when they have a nice new one to share.
That's all I remember, please send things that I forgot. Next telecon in 2 weeks, on Thursday, May 7 at 1:30 pm Eastern time.
cheers, thanks all! justin
Attachment:
On Thu, 23 Apr 2015 02:05:19 GMT, Justin Albert wrote:
> Hi! > > Telecon tomorrow (Apr. 23) at our usual time: 1:30 pm Eastern (10:30 am > Pacific, 19.30 European). Discussion items include: flight planning, > light sources and light source modelling, goniometric and pre- and > post-flight calibration, communications tests, new nanosat bus and > payload solid models, JHU progress, computing/website, grant > applications, and recap of schedules. A reminder of the CSA project > timeline is attached. > > Here's how to connect: > 1) Open Skype on your computer (note that of course, you should first install Skype, http://www.skype.com , on your machine if you haven't already). > 2) In the "Contacts" menu, add me ( jalbertuvic ) as a contact, if you haven't already. > 3) Just wait for me to Skype-call you at the usual time (1:30 pm Eastern, 10:30 am Pacific). > 4) If there is any trouble, or if you don't get a call for some reason and would like to join, just send me an e-mail (jalbert@uvic.ca). > > Here's the tentative agenda: > I) Flight planning > II) New diffused light source and its modelling, pre- and post-flight calibration, and goniometric calibrations > III) Communications tests (possible backup optical and radio, etc) > IV) New nanosat solid models from Houman and Cordell > V) Progress at JHU / STScI > VI) Computing/website > VII) Grant applications > VIII) AOB > > Talk to you all tomorrow, thanks! > justin > > Attachments: > http://projectaltair.org/HyperNews/get/AUX/2012/11/12/18.02-43361-Schedule-20120702_hqp.pdf >
